avoid depending on the message text for a cm-accomplice event

svn: r11355

collects/compiler/cm-accomplice.ss

@@ -4,4 +4,7 @@
 (define (register-external-file f)
   (unless (and (path? f) (complete-path? f))
     (raise-type-error 'register-external-file "complete path" f))
-  (log-message (current-logger) 'info "compilation dependency" f))
+  (log-message (current-logger) 
+               'info 
+               (format "file dependency: ~s" f)
+               `#s(file-dependency ,f)))

collects/compiler/cm.ss

@@ -112,6 +112,7 @@
 
 (define-struct ext-reader-guard (proc prev)
   #:property prop:procedure (struct-field-index proc))
+(define-struct file-dependency (path) #:prefab)
 
 (define (compile-zo* mode path read-src-syntax zo-name)
   ;; External dependencies registered through reader guard and accomplice-logged events:
@@ -136,9 +137,9 @@
                     (cond
                      [(eq? (vector-ref l 2) done-key) 'done]
                      [(and (eq? (vector-ref l 0) 'info)
-                           (equal? "compilation dependency" (vector-ref l 1))
-                           (path? (vector-ref l 2)))
-                      (external-dep! (vector-ref l 2))
+                           (file-dependency? (vector-ref l 2))
+                           (path? (file-dependency-path (vector-ref l 2))))
+                      (external-dep! (file-dependency-path (vector-ref l 2)))
                       (loop)]
                      [else
                       (log-message orig-log (vector-ref l 0) (vector-ref l 1) (vector-ref l 2))

collects/scribblings/mzc/make.scrbl

@@ -250,8 +250,8 @@ A parameter for a procedure of one argument that is called to report
 @defproc[(register-external-file [file (and path? complete-path?)]) void?]{
 
 Logs a message (see @scheme[log-message]) at level @scheme['info]. The
-message is @scheme["compilation dependency"], and the data associated
-with the message is @scheme[file].
+message data is a @schemeidfont{file-dependency} prefab structure type
+with one field whose value is @scheme[file].
 
 A compilation manager implemented by @schememodname[compiler/cm] looks
 for such messages to register an external dependency. The compilation